A few years before directing his debut feature, Cronos, the now Academy Award winner, Guillermo del Toro, was working in Mexican television helming episodes of a popular horror series called La Hora Marcada, where other major talents like Emmanuel Lubezki and Alfonso Cuarón also got their start.

At the time, Del Toro also created commercials, as many emerging moviemakers do to make a living. But even if it was work for hire, the master of monsters found a way to infuse his personal affinity for genre cinema into the mix.

Seven years ago, when the director was away from the spotlight and in between projects, Carlos Mezamar’s YouTube channel, which is dedicated to uploading vintage commercials from Mexican television, unearthed a gem from 1991 that is sure to make everyone’s love for the director grow exponentially.

The spot was commissioned by Alka-Seltzer, the famous antacid and stomach pain reliever, and was not only directed by Del Toro, but also stars the filmmaker in the lead role of a businessman who transforms into a werewolf after a big meal causes indigestion. “First he eats as a beast and then we have to alleviate his discomfort,” says the receptionist as a suit-wearing Del Toro heads into the bathroom twitching from cramps.

Channeling classics like Curt Siodmak’s The Wolf Man and John Landis’ An American Werewolf in London, Guillermo Del Toro transforms into hairy creature in front of a mirror, of course, when he chugs his Alka-Seltzer he returns to his natural state as clean-shaven young man in his mid-20s. He’s come a long way, but that irreverent sense of humor and creative approach appear to be intact.

Watch the hilarious clip for yourself:

 

[H/T: Cinema Tropical]